17 / 2021-06-23 09:24:44

Study on Corrosion Properties of Hydrophobic Coatings on 65Mn steel

65Mn steel, coating, hydrophobic

65Mn steel is often used to manufacture soil-engaging tools, which work in humid or corrosive environment with pesticides and fertilizers. This will result in the failure of the tools because the corrosion rate is too fast. In order to improve the corrosion resistance, hydrophobic coatings were fabricated successfully on the surface of 65Mn steel substrate by direct current electrodeposition. The influences of the working voltage and deposition time on the characteristics of the coatings were investigated. The results of scanning electron microscopy (SEM) and static water contact angle test indicate that the morphology, thickness and wettability of the hydrophobic coatings are significantly affected by the working voltage and deposition time. However, they have little influence on the phase composition. The X-ray diffraction (XRD) results reveal that the main phase composition of the coatings is calcium stearate. In addition, the influences of the working voltage and deposition time on the corrosion behaviors of the coated substrates are researched. When the working voltage is 80 V and the deposition time is 30 min, the best corrosion resistance is obtained. The superior protection effect is mainly due to the thicker and compact coating along with the higher water contact angle on the coating surface.